End slice mechanism



May 24, 1938. A. VAN VEEN END SLICE MECHANISM Filed July 26, 1955 I 2 Sheets-Sheet l 9 My TTORNEY I INVENTOR Patented May 24, 1938 UNITED STATES rnrlaztrr OFFICE END SLICE MECHANISM Application July 26, 1935, Serial No. 33,291

Claims.

This invention relates to improvements in sliclng machines of the single knife type, more particularly to bread-slicing machines, its main object being to eliminate the extremely thin end slices obtained with loaves which are shorter than the loaf-length for which the machine has been set.

Heretofore in the operation of machines of this type, when the loaves were inserted between the pusher plate and the forward end plate on the slicer conveyor, if the length of the loaf were less than the distance therebetween', there would be a gap between the forward end of the loaf and the end plate; and the thickness of the first slice cut by the movement of the knife across the path of the loaf would be the distance of the knife from the forward end plate less the gap between the loaf and the said end plate. The extremely thin slices thus produced are apt to crumble and thus detract from the appearance of the sliced loaf, particularly when wrapped.

To obviate this difficulty, the present invention provides means for tipping the pusher plate forward so as to move the loaf against the end plate and thus to close the gap before the loaf crosses the path of the slicing knife, and then to gradually return the pusher plate into upright position before the loaf has passed the knife, so as to assure slices of full thickness at the trailing end of the loaf. Thus, the variations in the length of various loaves from the predetermined length are distributed over a comparatively large number of the intermediate slices, and the difference in the thickness of the individual slices is so small as to be unnoticeable.

To this end there is provided an arm extend ing from the pusher plate and carrying a roller engaging in a cam track made up of three portions: a stationary horizontal portion, a vertically adjustable horizontal portion, and an intermediate portion which connects the end portions. At the beginning of each run, the adjustable portion of this cam track is set for the approximate maximum difference between the lengths of the loaves to be sliced, the individual variations of the loaf lengths within this maximum difference being compensated by the plasticity of the loaves. With this and other objects not specifically mentioned in View, the invention consists in certain constructions and combinations hereinafter fully described and then specifically set forth in the claims herewith appended.

In the accompanying drawings which form a part of this specification and in which like characters of reference indicate the same or like parts:

Fig. l is a side elevation of the end slice mechanism;

(c1. MSW-) Fig. 2 is an end elevation of the same, on line 2-4! of Fig. 1;

Fig. 3 is a diagrammatic end elevation showing the improved end slice mechanism in rela tion to a single-blade bread slicing knife;

Fig. i is a diagrammatic side elevation of the parts shown in Fig. 3; and

Figs. 5 to 8 are diagrammatic side elevations showing the different stages in the operation of the end slice mechanism.

In carrying the invention into effect there is provided means for continuously advancing loaves endwise, a continuously rotating knife arranged to periodically cross the path of the loaves to cut them into a series of slices, this means acting to advance the loaves in such relation to the movement ofthe knife that the thickness of the forward endslice cut therefrom will be constant and the thickness of the last end slice cut therefrom will be greater than that of the intermediate slices, regardless of variations in the length of the loaves. In the best constructions contemplated the knife may be of the single blade helical type and provided with a volute cutting edge, and the loaf-advancing means may include pairs of continuously traveling members spaced to receive loaves therebetween and advance them endwise, and mechanism for forwardly moving the trailing member of successive pairs, with respect to the leading member thereof, to assure engagement of the forward end of the loaf with the leading member of the pair, regardless of variations in the length of the loaves, this mechanism acting to thereafter retract the trailing member of each pair in order to advance the loaf in such relation to the movement of the knife that the intermediate slices will be cut thinner than the last slice. These various means and parts may be widely varied within the scope of the claims for the particular construction selected to illustrate the invention is but one of many possible concrete embodiments of the same. The invention, therefore, is not to be restricted to the particular construction shown and described.

Referring to Figs. 1 and 2, the loaf L to be sliced is delivered on a table Ill on which it is pushed in the direction of the arrow by a member such as a pusher plate ll supported by one of a number of carriers I2 attached to the connecting pins of an individual link of an endless chain !3 suitably driven from a shaft of the slicing machine. A member such as a plate H4 at the forward end of the loaf is propelled by a carrier l5 similarly attached to an endless chain it which runs parallel with chain [3 and may be adjustable lengthwise relative to the latter so that the distance between the pairs of plates H and I4 mounted on the chains can be set to lit the maximum length of the loaves to be sliced.

The carriers |2 and I5 are equipped with rollers l8 and I9 guided by cam rails 20 and 2|, respectively, to support the plates H and M in proper position.

To tip the pusher plates forward, each carrier I2 is provided with a rearwardly extending arm 22 carrying a roller 23. This roller engages with a cam track consisting of a stationary portion formed by two horizontal bars 24 and 25, of an intermediate portion formed by two bars 26 and 21 attached to bars 24 and 25 by pivot-pins 28 and 29, and of a vertically adjustable portion formed by two horizontal bars 30 and 3| attached to bars 26 and 21 by pins 32 and 33. The bars 30 and 3| are joined by cross pieces 34 and 35 attached to the ends of parallel levers 3B, 31, 38 and 39 on shafts 40 and 4| supported in bearings provided in the pedestal 42 of the slicing machine. The levers 31 and 39 are fast on shaft 4| and the last-mentioned of these 1evers, 39, has a handle 43 by which the bars 30 and 3| can be raised or lowered. To maintain the bars 3|] and 3| in the desired position a slot 44 is provided in handle 43 through which passes a screw 45 set in the frame 42 and, when tightened, holding the arm 43 in the adjusted position.

The operation of the end slice mechanism is as follows: The loaf L on the table it) between a forward end plate l4 and a pusher plate H is advanced by the latter toward the knife 46, Figs. 3 and 4, which may have a helical cutting edge with a lead equal to the desired thickness of slice and be mounted on a shaft 4! rotating in the direction of the arrow. When the loaf approaches the knife 46 the roller 23 on the carrier |2 of pusher plate enters the portion of the cam track between the adjustable bars 30 and 3|. The knife 46 may be of the type shown in the patent to J. J. Diamond, No. 1,973,526, granted Sept. 11, 1934, or co-pending application of Jensen and Van Veen Serial No. 713,174, filed February 27, 1934 to which reference may be had for the details of its construction and the mechanism for driving the shaft 41 in timed relation to the advancing movement of the loaf; or it may be of any other suitable single blade type.

If the bars 30 and 3| were set in alignment with the stationary bars 24 and 25, as shown in Fig. 5, the pusher plate would be maintained in upright position; and if the loaf L is shorter than the normal loaf length for which the plates |4 have been set, a gap G would be established between the end plate l4 and the forward end of the loaf L and the first slice would be cut eX- tremely thin. But when the bars 30 and 3| have been adjusted to a raised position, as in Fig. 6, the roller 23 on entering this portion of the cam track, the slack in the upper run of the chain I3 will permit the carrier |2 to be tipped forward with the plate thereby pushing the loaf L against the end plate I4 and filling the gap G and thus increasing the thickness of the first slice cut by the knife 46 so that it will be of constant thickness. As soon as the roller 23 has passed the joint 32, 33 of the cam track and while guided by the bars 26 and. 21, the plate I! is gradually returned to an upright position, so that a steadily increasing gap G is established between the forward end of the loaf and the plate M, as seen in Fig. 7 and slices of progressively increasing thickness are out. When roller 23 has reached the joint 28, 29 of the fixed portion 24, 25 of the cam track, this gap has attained its original width and the rear end of the loaf bears against the now upright pusher plate N, Fig. 8, so that the remaining slices are cut to the full thickness, which is greater than that of the intermediate slices.

Although the same is not shown in the draw ings, it should be understood that the loaf is pushed between a top tension plate and side guides (not shown) while being sliced. As the details of the same are fully disclosed in the Diamond patent and the co-pending application mentioned above, they need not be further described herein.

What is claimed is:

1. The combination with pairs of continuously traveling leading and trailing members spaced ln predetermined relation to receive loaves therebetween and continuously forward them endwise, a single blade rotary knife periodically crossing the path of the loaves forwarded by said members to slice the loaves into a plurality of slices, and means for forwardly moving the trailing member of successive pairs with respect to said leading member, to assure engagement of the forward end of the loaf with the leading w member of the pair, regardless of variations in the length of the loaves, whereby the first slice out from the loaf by said knife will be of constant thickness, and mechanism acting to thereafter progressively retract the trailing member i of each pair with respect to the leading member thereof in order to advance the loaf in such relation to the movement of the knife that the intermediate slices will be cut thinner than the last slice, whereby the last slice will be cut to a thickness greater than the intermediate slices regardless of variations in the length of the loaves.

2. Means for forwarding articles endwise, comprising an endless chain, members carried by said chain in normally upright position to advance articles endwise, and devices for successively tipping said members forward to displace the articles relatively to the chain and then gradually returning the members to upright position, said devices including a cam track having a stationary horizontal portion, an intermediate portion pivoted on said stationary portion, and a vertically adjustable portion connected to said intermediate portion, and said members each including a carrier fastened to said chain and provided with a cam roller arranged to enter said cam track and a pusher plate supported on said carrier to engage and advance an article, whereby said vertically adjustable cam track portion may be raised to set said intermediate cam track portion in a downwardly inclined position and cause the pusher plate to tip forward and displace the article when the cam roller enters the adjustable cam track portion and gradually return the pusher plate to upright position when the cam roller enters the inclined cam track portion.

3. The combination with a continuously rotating helical knife having a volute cutting edge, of a conveyor provided with a plurality of loaf engaging fiights for engaging the rear ends of loaves of bread and continuously advancing them endwise across the path of said knife, means for maintaining said flights in erect driving relationship with the rear ends of said loaves during all portions of their travel towards and past said knife, and additional means for tilting said flights forward in their path of travel to move said loaves on said conveyor to advance said loaves an additional amount towards said knife prior to its slicing engagement therewith, and progressively backward during the slicing operation, substantially in the manner and for the purpose set forth.

i. The combination with a conveyor provided with pairs of traveling members, each pair having a leading and a trailing member spaced in predetermined relation to receive loaves therebetween and forward them endwise, of a rotary knife having a helical cutting edge periodically crossing the path of the loaves forwarded by said members to slice the loaves into a plurality of slices, means for moving the trailing member of each pair forwardly with respect to the conveyor to assure the advance of each loaf into engagement with the leading member of the pair regardless of the variations in the lengths of the loaves,

whereby the first slice cut will be of constant thickness, and mechanism acting thereafter to retract the trailing member of each pair before complete slicing of said loaves in order to advance each loaf in such relation to the movement of the knife that the intermediate slices will be cut thinner than the last slice, said mechanism being so constructed and arranged that the last slice will be cut to a thickness at least equal to that of the intermediate slices regardless of the length of the loaves.

5. The combination with a continuously rotating knife, and a conveyor provided with a plurality of pairs of loaf positioning members, each having a leading and a trailing member, of means for continuously moving said conveyor to advance loaves endwise across the path of said knife, means for maintaining said trailing members in substantially vertical position in contact with the rear ends of said loaves during a portion of the travel towards said knife, means for moving said trailing members forward independently of the movement of said conveyor to advance the front ends of said loaves against the front members as said loaves approach said knife, and additional means for returning said trailing members to substantially vertical position so that said loaves may drop back during their progress across the path of said knife, whereby the last slice cut from said loaf is at least equal to the thickness of the inter mediate slices.

6. A bread slicing machine having the elements combined and cooperating as set forth in claim 4, in which said means for causing forward movement of the trailing member with respect to the conveyor is so disposed relatively to said knife that the trailing member is moved forward at a distance from said knife of at least the length of a loaf.

7. A bread slicing machine having the elements combined and cooperating as set forth in claim 5, in which provision is made of a volute knife, and in which the means for effecting advancing movement of said conveyor, and said rotating volute knife, are so coordinated and timed that the convolutions of the knife avoid contact with said trailing members, and the rotation of the knife effects a cutting action substantially equal to the thickness of a normal slice, in the rotary travel of the knife blade volute immediately before a trailing member passes the knife, and immediately after it passes the knife.

8. The combination with a helical knife having a volute cutting edge, and means to rotate said knife continuously, of a conveyor provided with a tilting loaf-advancing flight for engaging the rear end of a loaf of bread, and for feeding said loaf continuously across the path of said continuously rotating knife; means to tilt said flight forward to an extent equal approximately to the predetermined thickness of a slice of said loaf, and thereby to present the leading end of said loaf for severance therefrom by said knife of an end slice conforming substantially to said slice thickness; and means to retract said flight progressively during advancement of said loaf by said conveyor during the slicing operation, to a total extent equal substantially to said predetermined slice thickness, thereby to present the trailingend of said loaf to said knife for severance of a heel of similar thickness.

9. The combination with a single helical knife having a volute cutting edge, and means to rotate said knife continuously, of a conveyor provided with a plurality of tilting loaf-advancing flights each adapted to engage the rear end of a loaf in a series of loaves supplied to said conveyor successively, and said flights being adapted to feed said loaves in succession continuously across the path of said continuously rotating knife; means to tilt each flight forward to an extent equal approximately to the predetermined thickness of a slice of bread and thereby to present the leading end of each loaf for severance therefrom by said knife of a heel of approximately said slicethickness; and means to retract each tilting flight progressively during advancement of its corresponding loaf by said conveyor, to a total extent equal substantially to said predetermined slice thickness, thereby to present the trailing end of,

said loaf to said knife for severance of a heel approximating the first-named heel in thickness; said tilting flights being each adapted, in the course of its progressive retraction, to present the portion of the loaf, intermediate its said heels, for complete severance into slices each approximating sensibly the average thickness of said heels, and thus to apportion said loaf into slices of fairly exact standard individual content, said apportionment being effected automatically in conformity to the length of each loaf as it is being sliced, thus compensating for variations in loaf length.

10. The combination with a continuously rotating helical knife having a volute cutting edge, of a conveyor provided with a plurality of loaf engaging flights for engaging the rear ends of loaves of bread and continuously advancing said loaves endwise across the path of said knife, means carried by said flights for maintaining said flights in erect driving contact with the rear ends of said loaves at all times during their travel towards and past said knife, and devices for tilting said flights forward and backward in said erect driving position to vary the disposition of the loaves upon the conveyor, and relatively to the path of the knife, means to rotate said knife at a predetermined speed, means toactuate said conveyor, and means for co-ordinating the movement of said conveyor and said tilting movements of said flights with the rotative cutting strokes of the knife, to avoid collision with said knife, and said forward and backward tilting being timed to compensate for variations in length, as between successive loaves, and thus to insure a sensible conformity to a predetermined slice thickness throughout the loaf, including both end slices.

ANTON VAN VEEN. 

